Test results from water samples indicate the algal bloom is in fact harmful. Owen Govender, Marine Ranger for the Knysna section of the Garden Route National Park says ‘Professor Brian Allanson of the Knysna Basin Project has concluded the algal bloom is harmful to filter feeders. Such include muscles, oysters and shellfish.’
Today the Action Pollution Committee (SANParks, Knysna Basin project, Knysna Municipality and the Eden District Municipality’s Health division) confirmed measures to ensure the public remain informed.
All users of the coastal environment are advised not to eat shellfish or any dead fish that wash up on the shore.
The committee also decided planned water activities such as the Rotatry Splash festival and the Lagoon Mile swim in Knysna would proceed. There is no evidence of people who have died from swimming during a red tide.
The bloom has now stretched to as far as Mosselbay. It started in Algoa Bay and spread to Tsitsikamma (10th December 2015).
Visitors are mesmerized by the beauty of the red tide at night, how red coming out of the blue provides spectacular viewing!
What causes a red tide (Microbial Life Educational Resources, online): ‘Red tide is a phenomenon caused by algal blooms (Wikipedia definition) during which algae become so numerous that they discolor coastal waters (hence the name “red tide“). The algal bloom may also deplete oxygen in the waters and/or release toxins that may cause illness in humans and other animals.’